Stove



July 7, 1942. J.. E. CHAMBERS' STOVE Filed Oct. 11, 1937 2 Sheets-Sheetl INVENTOR. fin/vfi Cimnasles,

ATTORNEYS.

July 7, 1942. J. E; CHAMBERS STOVE Filed Oct. 11. 1937 Sheets-Shut 2ATTORNEYS.

Patented July 7, 1942 UNITED STATES PATENT OFFICE STOVE Jchn E.Chambers, Shelbyville, Ind. Application October 11, 1937, Serial No.168,323

(c1. 12s-a9) 18 Claims.

In gas ranges employing a thermostatic control of oven temperature it iscustomary to provide a pilot burner and a main burner and to regulatethe supply of gas to the latter by means of a, temperature-responsivevalve. One difiiculty encountered in such an arrangement arises from thefact that the temperature-responsive valve, because of slow opening orslow or imperfect closing, will under some conditions pass gas at a rateinsuflicient to maintain combustion at the ports of the main burner. Toovercome this difliculty, it has been proposed to install around thetemperature-responsive valve a by-pass which will provide gas-flow atthe minimum rate required to insure maintenance of combustion, and toemploy the temperature-responsive valve only to vary gas supply over arange above this minimum rate.

The by-pass arrangement just described is open to the objection that inorder to insure against extinguishment of the flame in a main burnerhaving sufiicient capacity to raise the oven to the maximum desiredtemperature within a satisfactorily short time, the minimum rate of gasflow provided by the by-pass is too high to be economical and,especially in the case of an insulated oven, too high in some instancesto prevent oven temperature from rising unduly above the value at whichit is desired to maintain it.

It is the purpose of my invention to overcome the difliculties abovenoted and to provide a gas burner which will operate at maximumefficiency when supplied with its full quota of gas but which willproduce a stable flame at minimum rates of gas-flow considerably lowerthan any possible with safety in prior arrangements. A further object ofmy invention is to provide an arrangement in which gas leaking past anearly closed temperature-responsive valve in quantity insufficient ofitself to maintain combustion will nevertheless be burned and preventedfrom escaping. Still another object of my invention is to eliminate thenecessity for a pilot burner as a separate element in association with athermostaticall controlled main burner.

In carrying out my invention, I form the burner with two independentpassages for the combustible mixture of gas and air, and I provide eachof such passages with aseries of discharge orifices. The supply of gasto one of these passages is controlled by an automatic valve responsiveto oven temperature, while the supply of gas to the other passage isfixed at the minimum rate necessary to maintain combustion at theorifices of that passage. The main gas passage,

" primary air.

or that associated with the automatic valve, has each of its dischargeorifices arranged in igniting relationship to an orifice of the otherpassage, so that any gas escaping from the mainpassage orifices inquantity insufficient to maintain combustion will burn with the gasemerging from the orifices of the other passage.

The accompanying drawings illustrate my invention: Fig. 1 isa horizontalsection through the oven of a gas range, showing my improved burner inplace therein; Fig. 2 is a fragmental vertical section on the line 22 ofFig. 1; Fig. 3 is a vertical section on an enlarged scale on the sectionline 33 of Fig, 1; Fig. 4 is a plan view of a .modified form of burner;Fig. 5 is a vertical section on the line 55 of Fig. 4; Fig. 6 is avertical section on the line 6-6 of Fig. 4; and Fig. 7 is a section onthe'line 'l! of Fig. 5.

The oven l0 illustrated in the drawings has insulated walls H and asuitable door I 2. The burner, which is disposed in the oven a shortdistance above the floor thereof, is hollow and, in the arrangementshown in Figs. 1 to 3, substantially U-shaped in plan. The interior ofthe burner is divided into two passages l4 and I5 by a partition l6which extends from one end of the burner to the other in spaced relationto the side walls thereof. Communicating with the passage I4,conveniently at the middle of the intermediate leg of the U-shapedburner, is a main mixture-suppl conduit l1 formed near its inlet endwith a venturi l8 and provided with a conventional mixing valve IQ forthe admission of A similar conduit 11', having a venturi I8 and mixingvalve Iii, communicates with the gas passage I5 of the burner. Theburner is provided with a series of discharge orifices 22 for thepassage l4 and with a second set of discharge orifices 23 for thepassage [5. Each orifice I5 is disposed adjacent an orifice M, and eachsuch pair of adjacent orifices is desirably located at or near thebottom of a recess or port 2| provided in the burner above the partitionl6.

Gas for the two mixture conduits I1 and I1 is supplied from a main gasline 25 and through two branches 26 and 21 to the mixing valves 19 andI9, respectively. In the branch 26, I provide an adjustabletemperature-responsive valve 28 controlled by a temperature-responsiveelement 29 associated with the oven lit, and in the branch 21 I providea manually controlled valve 30 adapted for adjustment to a fixedposition controlling the minimum supply of gas to the burner. A main gasvalve 3| located in the main supply line is employed to shut off thesupply of gas to both branches 25 and 27.

In operation, the valve 3| is opened and the burner ignited, preferablyat one or more ignition ports 33 provided in the burner at the pointwhere the conduit l1 joins the passage l5. If the oven is cold at thistime, the temperatureresponsive valve 28 will be open, and gas will besupplied through the conduits I1 and II to both passages I4 and I5. Gasfrom both such passages will pass through the openings 22. and 23 intothe ports 2| and will emerge from each port, in effect, as a singlestream. As the temperature of the oven approaches that for which thevalve 28 is set, the temperature-responsive element 29 will operate tocontrol the valve 28 in such a way as to maintain the desired oventemperature. As the valve 28 moves toward closed position underregulation by the temperature-responsive element 29, the amount of gassupplied to the passage M will be decreased and will eventually reach apoint at which it would be insufiicient of itself to maintaincombustion; but because all combustible material passed by the valve 28emerges from the orifices 22 in proximity to the burning gas from theorifices 23, any small quantities of gas leaking past the valve 28 whennearly closed will be consumed. If the temperature-responsive ele- 'ment29 completely closes the valve 28, the only gas received by the burnerwill be that supplied through the conduit IT to the passage l5. Thevalve 3|] is so adjusted that this amount of gas will burn with a verylow flame which will cling to the walls of the port 2| and will bestable.

It is to be noted that the path traversed by the gas supplied throughthe valve 30, conduit Il', passage I5, and openings 23 is entirelyindependent of the path over which fiows the gas controlled by thetemperature-responsive element 29. Because of this, the diameters of theopenings 23, the cross-sectional area of the conduit II, the shape ofthe venturi I8, and the mixing valve I9 can be such as to provide forthe most efficient burning of the minimum supply of gas and for a gasvelocity sufficient to prevent back-firing, while the openings 22,conduit l1, venturi I8, and mixing valve I9 can be designed for mosteflicient operation of the main gas supply.

In the modification of my invention illustrated in Figs. 4 to 7inclusive the burner is of an elongated shape and is intended to extendtransversely across the oven l3 preferably near the front end thereof.The burner comprises two elongated portions 4|] and 4|, the formerhaving a longitudinally extending central opening in which the latter isreceived. If desired, the two portions 40 and 4| may be formed as partsof a single casting, being joined together by bridgelike members 42. Theportion 48 is hollow to provide a mixture-passage 43 communicating witha mixture-supply conduit 44 which joins the portion 40 conveniently nearits center. The portion 4| is likewise hollow to provide a passage 45communicating with a mixture-supply conduit 45.

The side walls of the burner-portion 4|, as is clear from Fig. 6converge upwardly to a relatively narrow top wall which is disposedbelow the upper surface of the burner portion 45 and in which I providea row of discharge orifices 48. The main burner portion 45 is providedwith discharge orifices 4}] along the sides of the central opening. Tobring the orifices 49 as close as possible to the orifices 48, thecentral opening in the main burner-portion is constricted at a pointnear the top of the burner-portion 4| and the sides of the centralopening diverge upwardly above such constriction. The mainburnerdischarge orifices 49 are located in such upwardly diverging side wallsto discharge obliquely upward above the burner-portion 4|. Desirably,the orifices 49 along one side of the central opening in the main burnerportion are staggered relatively to those along the opposite side toavoid impingement of the respective flames; and each of the orifices 43in the burner portion 4| is disposed midway between two orifices 49 onopposite sides of the central opening.

Below the constricted portion of the central opening in the mainburner-portion the side walls thereof diverge downwardly in spacedrelation to the burner-portion 4| to provide passages 59 for theadmission of secondary air.

In an arrangement such as that described, the mixture-supply conduits 44and 45 may be brought outwardly through a side wall 53 of the oven wherethey are adapted to receive gas respectively from the conduits 25 and2'! illustrated in Fig. 1. As, is clear from Fig. 4, the supply conduits44 and 46 are enlarged beyond the side wall 53 of the oven to formchambers 54 each of which has an air-admission opening in its rear wall.The efiective area of each of these openings may be regulated by a disk55 supported on the rear end of a screw 55 which is screw-threadedlymounted in the front wall of the associated chamber 54 and which hasassociated with it a lock nut 51. Conveniently, the outer ends of thetwo conduits 44 and 45 are offset vertically so that both screws 56 areaccessible from the front of the stove.

The passage 43 need not be continuous around the central opening. As isclear from the drawing, such passage is interrupted by a solidbridgemember 60 located centrally of the burner on the front sidethereof. Conveniently, the upper surface of this bridge is located belowthe top of the burner-portion 4| so that it will be possible to observe,through a sight-opening (not shown) in the front wall of the oven,whether or not there are flames above the orifices 43 of the innerburner-portion 4|.

The construction illustrated in Figs. 4 to 7 possesses all theadvantages of that shown in Figs. 1 to 3. It has the further advantage,however, that only one half as many auxiliary orifices 48 are necessaryto have one closely associated with each of the main orifices 49. I canthus increase the difference between the minimum and maximum capacitiesof the burner.

I claim as my invention:

1. In a gas range, a burner comprising a hollow member, a longitudinalpartition within said hollow member dividing its interior into twoindependent mixture passages, said burner being provided exteriorly witha row of recesses substantially co-planar with said partition, each ofsaid recesses communicating independently with said passages, supplyconduits of different crosssectional areas for the respective gaspassages, and a temperature-responsive valve associated with the supplyconduit of larger cross-sectional area.

3, A gas burner having a series of burner ports and two independentmixture supply passages independently communicating with each of saidports through restricted openings, the openings through which onepassage communicates with said ports being smaller than the openingsthrough which the other passage communicates with said ports.

4. A gas burner having a series of burner ports and two independentmixture supply passages independently communicating with each of saidports through restricted openings.

5. A gas burner having a series of burner ports and two independentmixture supply passages independently communicating with each of saidports.

6. A gas burner having two independent mixture supply passages eachhaving a series of discharge orifi-ces, said orifices being arranged inpairs with the two orifices of each pair communicating respectively withsaid two passages, and a common port for each such pair of orifices.

7. A gas burner, comprising a U-shaped tube, a partition extending fromone end of said tube to the other and dividing the interior of the tubeinto two independent mixture passages, a U-shaped row of burner portsco-planar with said partition and each communicating independently withsaid two passages, and two supply conduits communicating respectivelywith said two passages at points located on opposite sides of theintermediate leg of said U-shaped burner.

8. The invention set forth in claim 7 with the addition of means forindependently controlling the supply of gas to each of said supplyconduits, the control means associated with one conduit beingtemperature-responsive.

9. A gas burner provided with a supply passage having a row of upwardlydirected discharge orifices, said burner also being provided with asecond supply passage having two rows of discharge orifices located onopposite sides of said first passage and discharging generally towardeach other over the orifices therein, and means for independentlysupplying gas to said two passages, said means including atemperature-responsive valve controlling the supply of gas to the secondpassage.

10. A gas burner provided with a supply passage having a row of upwardlydirected discharge orifices, said burner also being provided with asecond supply passage having two rows of discharge orifices located onopposite sides of said first passage and discharging generally towardeach other over the orifices therein, and means for independentlysupplying gas to said two passages, said means including atemperacure-responsive valve controlling the supply of gas to one ofsaid passages.

11. A gas burner provided with a supply passage having a row of upwardlydirected discharge orifices, said burner also being provided with asecond supply passage having two rows of discharge orifices located onopposite sides of said first passage and discharging generally towardeach other over the orifices therein, and means for independentlysupplying gas to said two passages.

12. A gas burner, comprising a hollow elongated central portion, ahollow outer portion embracing said central portion but spacedtherefrom, and conduits for supplying gas independently to the interiorsof said hollow burner-portions, said central burner-portion beingprovided with a row of upwardly directed discharge orifices and saidouter burner-portion being provided With two rows of discharge orificeslocated on opposite sides of and discharging generally toward each otherover the row of orifices in said central burner-portion, the orifices ofsaid outer portion being inclined upwardly toward said central portionto discharge obliquely thereover.

13. A gas burner, comprising a hollow elonated central portion, a hollowouter portion embracing said central portion but spaced therefrom, andconduits for supplying gas independently to the interiors of said hollowburner-portions, said central burner-portion being provided with a rowof upwardly directed discharge orifices and said outer burner-portionbeing provided with two rows of discharge orifices located on oppositesides of and discharging generally toward each other over the row oforifices in said central burner-portion.

14. A gas burner having a main mixture supply passage and a smallerauxiliary mixture supply passage independent of each other, each of saidpassages being provided with a series of discharge orifices, theorifices in said auxiliary passage being directed generally toward theorifices of the main passage whereby any gas emerging from the orificesof the main passage will be ignited by the flames from the orifices ofthe auxiliary passage.

15. The invention set forth in claim 14 with the addition of means forindependently controlling the supply of gas to each of said passages,the control means associated with said main passage beingtemperatureresponsive.

16. The invention set forth in claim 14 with the addition that theorifices associated with said auxiliary passage are smaller than thoseassociated with the main passage, and temperatureresponsive meanscontrolling the sup-ply of gas to the main passage.

17. The invention set forth in claim 14 with the addition that theorifices associated with said auxiliary passage are smaller than thoseassociated with the main passage.

18. The invention set forth in claim 14 with the addition that theorifices associated with said auxiliary passage are smaller than thoseassociated with the main passage. and supply conduits for said twopassages respectively, the supply conduit -for the auxiliary passagebeing smaller in cross-sectional area than the other supply conduit.

JOHN E. CHAMBERS.

